Two Republican senators are accusing the State Department of misusing taxpayer dollars by green-lighting $500 million for a United Nations climate change program without first obtaining congressional approval.

The senators now are demanding the department justify the “cloak-and-dagger” contribution to the Green Climate Fund (GCF) – even threatening legal action.

Gardner, in a statement to FoxNews.com, alleged the department was trying to “wave a magic wand and write a half-billion dollar check to a Green Climate Fund that they admit was never authorized by Congress.”

He also vowed to “pursue legislative action that prevents cloak-and-dagger re-programming of money outside of congressional approval.”